Virtual dissection by ultrasound: probe handling in the first year of medical education

Objectives The aim of the present study was to assess the educational plan of first-year students of medicine by analyzing their scores in ultrasound body scanning. Methods Since 2009, the San Paolo Medical School (Milan, Italy) has vertically integrated the study of anatomy with ultrasound-assisted virtual body dissection. Three modules were supplied: musculoskeletal system, heart and abdomen pelvis. 653 first-year students were trained. The students alternated as mutual model and operator. A skillfulness score was assigned to each student. The scores were consequently listed. Nonparametric exact multiple contrast tests were employed to determine relative group effects. Results Statistical analysis showed that: no gender-related differences were found (0:49; p = 0.769); peer learners performed less well than peer tutors (0.677; p = 0); between modules, scores in the musculoskeletal system (pMS = 0.726) tend to be higher (p < 0.001) than those obtained in the heart and abdomen pelvis (pH = 0.398; pAP = 0.375 p = 0.270); significant differences were found compared to the beginning of the project\u2019s academic year. Conclusion The students considered this didactic course an engaging and exciting approach. Acceptance of peer teaching was extraordinarily high. Autonomous exercitation allowed the students to improve self-criticism and enhance their own skills. The level of expertise obtained by peer tutors and by peer learners can be considered satisfactory. The main objective of training future physicians on personal stethoechoscope with the necessary competence seems to have been successfully started

Constraints on cosmic strings using data from the first Advanced LIGO observing run

Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such signals was found in the data, and as a result we set upper limits on the cosmic string parameters for three recent loop distribution models. In this paper, we initially derive constraints on the string tension Gμ and the intercommutation probability, using not only the burst analysis performed on the O1 data set but also results from the previously published LIGO stochastic O1 analysis, pulsar timing arrays, cosmic microwave background and big-bang nucleosynthesis experiments. We show that these data sets are complementary in that they probe gravitational waves produced by cosmic string loops during very different epochs. Finally, we show that the data sets exclude large parts of the parameter space of the three loop distribution models we consider